Apparatus for preparing and spraying



July 15, 1952 w. G. BROWN ETAL 2,603,462

APPARATUS FOR PREPARING AND SPRAYING CEMENTITIOUS MATERIALS 4 Sheets-Sheet l Filed March 19. 1949 Myx/ Y ATTORNEYS.

July l5, 1952 W, Q BROWN ETAL 2,603,462

APPARATUS FOR 'PREPARING AND SPRAYING CEMENTITIOUS MATERIALS Filed March 19, 1949 4 Sheets-Sheet 2 E- l M526 /09 E-L Warren' Bran/)7.

ATTORNEYS- July l5, 1952 w.A G. BROWN ETAL APPARATUS FOR PREPARING AND SPRAYING CEMENTITIOUS MATERIALS 4 Sheets-Sheet 5 Filed March 19. 1949 INVENTOR-S. Maffe/7 (gru/r, Bg/drrcf? .E Z/vnd?.

July 15;"1952 w. G. BROWN ETAL 2,603,462

APPARATUS FOR PREPARING AND SPRAYING CEMENTITIOUS MATERIALS Filed March 19, 1949 K 4 Sheets-Sheet 4 Patented July 15, 1952 yAPPARATUS Foa PREPARING AND 'sPnAy ,i if i f INGCEMEN'rrrIoUs MATERIALS A' Warren `Gnrovvn and Warren Durand Brown", y Y

' Detroit, Mich.

Application March 19,1949,serial-Natma; o

` claims; (o1. 2.591415@ The present invention relates to animprovedA apparatus for preparing and spraying cementitious materials suitable both for the Weatherproong, Waterprooiing and restoration of existing masonry and for the construction of new concreter structures. More particularly it relates toisuclran apparatus capable of preparing and applying cementitious materialswhich upon setting will be substantially free of shrinkage cracks and have greatly improved strength over that of similar materials prepared and applied by previ- The present application is a continuation-impart of our copendlngapplication.` for patent..Serial.No."514,042,1iled Decernf.

ously known apparatus.

ber13,-1Q43, 'which' was aV division of our, applica-1;

tionforpatnt; Seria1No.,46'.7,680; filed December t 3:.;1942, 'copendingrtnerewitn whichrappucations are-'now abandoned;` Y'

f-rriof to the-,present invention cementitious m'aterials'have been prepared and applied `in'fa. largev'variety of ways, each-of 'which has been at,v tendedwithgreater or less difficulties and none' of whicn'haveproduced a satisfactory product.

substantiallyl f reeV o fshrinkage cracks.`E lnzsome. instances it wasattempted to applyQ the material.

asa 'coating -bybfrushing iton.-^'Ihis-required tediousm'anual effort and the material 4wouldanot stayI uniformly mixed. Also, itfwas dicult to' obtain a; smoothly distributed coating. vIn all cementitious materialspreparedj and put in placef by previously known apparatus, thematerial hadv ash'rinkage 'factorof vepr cent aridl'afrelat'iv'ely low v'crushingstre'g'thfcompared-to' that ot fria-5?' ti'fil' Prepared aridT applica tyi-thepresentami 1 I l coatings; have -a'lrgenumber of minute? shrink' age cracks. This not only preventedtliatfslid unitary appearancewhich'is desirable inla'suryface :coating-,etui alsdand what is. much1 more important, constituted a gvery serious Vstructural defect in that thesecracks permit'a'weathering ofi-the-fcoating, 'causing these cracks to1 gradually wldenl and eventually-'Work 'entirely-through'theI coating andexposethelicoated structure;

vention-to rprovide an improved apparatus for pre-J paring land' 'applying cementitious coatingsffor. the vveatherproofing,` waterprooiingandf restora" ti'onf-of masonry, which,upo'n settingfwill'b'e sub-V stantially free of shrinkage cracks. Y V

"Y"-Acc`orilingly',-'it is ani object of thepresent in-f that when cement groutsare mixed in such'egurip; 1

ment, arelatively low(hydrationl of the ycement particles is obtained and much of the Water in. the material at the time that it is .put in placeisfin the form of free waterv mechanically held. The rate of evaporation of such water is muchI greater than, the rate at which such water will bev taken up as Water of hydration, under the atmos-l pheric conditions to which the material is subject when in position- Eorgthis reason much off'the Water present inthe groutY as -lfree Water at the time of application `vvllevaporate and vrnot-be. taken up as vWateraof hydration; This evapora-V tion leaves voids which resultV in the abovef.

mentioned shrinkage cracks., An examination of` drated. 1

- particles of which are muchmore uniformly v.and

Accordingly, another object of the inventionvisf to provide an improvedapparatus for-mixing and' applying cementitious'materials in which the hydration: of; the Y cement particles thereof, .,at'the time of puttingxthe material in place,is greatly improved. .f

It is also an object of the invention to providean apparatusy for preparingand putting in place cementitious materials 'having a much greaterr crushing strength than that of such materials, f

prepared" by any previously'known equipment'. t A further object of the inventionv is .f togprovide an apparatus for' mixing" and applying cementi.;y tious materials, Awhich, when -put in place, are more uniformly'mixed" than is possible with mas,

equipmentfjf i. Y Y

Another cbje'ct of the invention is to provide.. an apparatus of thetype above-indicated'which.. is capable-'of continuous operation to provideavj continuous supplyl of cement'igrout the cement,

terialsmixed and appliediby,previously-known. Y

highly hydrated than the cement lparticles yor material `prepared by' previously 1 known equip-1l ment so that 'an operator may continuously putI place, -without interruption, a cementitious.,l material 'whichafter setting and hardening willv be substantially free-of shrinkage cracks. r A further .obj ect of the invention' is toprovide an apparatus of thetype indicated above, including. improved self-cleaning `tanks adapted to pre-1 4 vent materials :from collecting-onthe inner sunfaces vof the tanks to form partially-set,orghardf;

v, L 1 1.*21, .g I These shrinkage cracks, Common iQz-mehtil tious;` materiels. prepared .in prei/mush' k'own.. equipment, result, at least in-part, from the Vfact" construction and reliable and efficient in opera-` I l .1515, itozopenfthecover-20and it should be noted that 'materials .Y

It'isvals'o an object of the invention to provide i an apparatus of the type indicated above, in-

4 inwardlyturned flange 23 Von the lower edge of the hopper. For moving the cover 20 upwardly, a link 2'4 is pivotally connected, as indicated at 25, to a projection 26 on the cover and this link cluding an improved stuing box adapted to pro- 5 in turn at its upper end is rigidly fastened to videV a bearing for rotatably supporting a shaft t passing through the Wall; of a tank Ycontaining cementitious materials under pressuregand preegl vent entrance ofthe grout into the `be'arin'g.

Another object ofthe invention isto providewjl07H32:V Y an apparatus ofthe type indicated above. includel ing a spray gun having an improved fadiustablef..

nozzle which is simplev in design, 'econ'or'nical oft tion. I

A further object of the invention is to provide" an apparatus of the type indicated'above;includeA ingan improved nozzle adapted to receiveY andV spraya thick 'mixture of...liquid and solidina'te rals. v

:Otheriobjectshoff thel inventionlwillfv become. Y

apparentfrom'the followingspecifi'caationg-lfrom?l thei-"drawingse relating thereto,l andi from-fthe: cla'rn'srhereinafter?setlforth.

reference may be had! to the-fdrawings `wherein Figure 1"l isgaf side elevationalview of i apparatus constructed? accordingj to lone form'off thewinven'j Figs-2)A isi a plan* View#A of thel apparatus shown; 30

y Fig-drie#aL-oross-sectionaliviewfof a'-valve`em'Y 40' other andistationaryelementsfilffastenedtolthe;V

pi'yed'in tlie-conduitaconecting theV tanks; v i

Fig. 8 is a sideelevational view of apparatueconstructie@ accordingisto another.' forma offthe inventioniandshowinglparts brokenaway.; 1

Figa 9 is:abrokengandienlarged sectionalfviewe 45 i 43.; andA :disposed:respectively at, theylower and.

ofthe-apparatusaillustratedsini'ig; 8; taken. sun stantiallyalongfthe' 1ine29+9 thereofjr n Fig. 10 is a plan view of the apparatus:illus-:-I

tratediimFigLSg -V .1'1 isiaxbrolienzand 'enlarged end-elevatifonvY 50, alvieur. ofc the apparatus:illustrated,inVv Fig; 1 0;n takenisubstantially from theilinezli-fld thereofz.

ofi;thezapparatusiillustrated in iiggilofltakenisubstantially alongithe line: IZaJ-I2fthereof; anda;` Y 5 .Eigz :1.35 is aibroken-.and enlargedsectional View.

oithe'valveiinpthe conduitconnectinggthemanlrs; Y

oftheapparatusjllustratedin Figs; Sand-105i f Referring to Figs. 1, 2 and 4, the apilalatusin:

has an opening l 'I 'throughzwhich the-'lovverf end:

' ofi'a' hoppen'lprojects: Theghopperandiyupperv endwallz'of-:vthe tankf'mawbawelded togetheraround? the; edge; of: the; opening.; sot as; toirobtain; a rigid asiwellasriseale'dzjoint: Y A` coverl 20iszprovide'ch at the-.lowererrdo the or-weidedi to the sidepf the hopper. ,ileyerfiffisgswung clockwise, as seen in Fig. 4,

one.' better understanding of1`the-invention,-2

a pair of toggle straps 28. The straps in turn connectedfatan intermediate point'31 y'to a bar This bar is rigidly fastened, as indicated *33, Ito the'tank, and may be similarly fastened When the the straps 2.8 and link 2li will be so moved asv argil-loil'calcareous gsub'stancelf such't aseEortiand c'erhenta' suitablelagg'regate suchiasnelydivida; ed--sai-nd', fand water, .although it.' should.berundere' sto@elf'tl'at-cntherl ingredientsgsuchias ;water-p roof -w ingi-agentsfma'ybe added; or 'thatdzhe mixturefmay comprise :i variousv other combinationsincluding,` Portland; or similar, cement..h f One; partizcement; three fpa'rts: sand,l andV` enough water; to provide thej required liquid conditioni may; 'be' used for? instance;and:theseingredientszarepplacedgin'. the.` tank'il 5-in properp'roportions,l and vthen'ithe;coverfA 25ilisfclsed 1 y t For:agitating:andimixingzfthe materials-. in; thee tank-z I 5,; .ax-rotary shaft: L31.. extends Y upwardlyg. i through. the.; bottom: .wall ,ofrthefz tanlg; andi this;

sli'aftiskeyed to the .upperiend f wall' B gofg asleevez 391. having radially :projectinggelements 'A Dgfzlat: spaced points thereon for stirringgthe.:materiale. iri's-tlrie.I tank; These elements `move infbetween inner. sideof th'ei.tank, andfromjthisit willg appreciatedithatrgthoroughstirring and-.mixingy of; thefmaterialfmay; be obtained. Theshaf-tfl is. rotatable in"a:.stationary; tube; 42s fastened tightly intlthegbottomzfwallv of theftanki by threaded-nuts:

upper;J sidesnoff, the wall. Atits upperzend. the; tube; 42has thrust bearing-: `115 whichVV engages.. the end wall 38f-inthefsleeveand'anut 48 onthe., upper en dfqfithe zshaft 31 .retains the sleeve 39,. tube .A25- and:shaft;assembled.Y

Below-'the bottom-wall, a =belel.gear :E fihskeyed. toithe; :loweriend Jef; thev Shaft an@ .this *gear Sum* stantiallyg abuts-j-afpacling gland 5 1 threaded-.on

f; the lower end of the tube' 42. A nut52'is-pro.-

vided on 'theflovver end'fof the shaftafornholdiln'g the gea-r yinplace, andl it.- will A.'be-y noted, tfltia. greaseiittingji3dsprovided;whichl communicates.. with manualpassage .54 in thefshaft-.ieadinggte the external;surface,ofthe-latter, from whichitf.

iti; willibe: seen .thatl leakage; ofgmaterial in; the.

fOllOWsf, that the outer -f surface fof tneg' pin may. k

Y For rotating the shaft 31, a second bevel gear 60 meshes withthegear '50. and this second bevel gear tis fastened to -a shaft ilV which, ,as best shown by,Fig-ure .1,- is connected to a reduction gearing box ,62; The reduction gearing is conf nected to afshaft 63of amotor 64, and from this.

it 4follows that the vagitator and mixer within'the tank I5 maybe rotated at a desired speed.

, Wlthrespect to mixingof the materials in the tank AIS, it'has been foundthat faster and much-v greater hydration of the cement particles occurs if the mixture is maintained under substantial pressure. Whereno pressure on theA materials is provided, fc'onsi'derable time is required for the cementparticlestol take up water in hydratingand furthermore only ,-.a relativelylow hydration is obtained, lDuringhydrationI or taking up of water, the'cement particles increase in volume, andwhere insufficientfhydration has occurred, it has vbee'n found thatr during setting of the material afterit isput in .placa the material shrinks adleaves'iine, hairline cracks. Where the ma# terials are maintained under substantial pressure during 'mixing and agitation, the air appears to be'forced out of thecement particles and a substantiallyv higher and more uniform hydration of thel'cement particles `is e'ieciaed..than may' be o btainedi'n materials preparedby previouslyknown shrinkage cracks obtainedin material prepared and-appliedy by. previouslyknown apparatus, in

w ich'a relatively low hydration ofthe cement particles is obtained, arepractically eliminated.

an instance ofvpressure which, has been found desirable for obtaining lthese results, an air line pres'sueof -approximately 100 pounds per square inch maybe used. f The-extent to which the present apparatus eliminates shrinkage cracks is' indicated by the fact that a recent visual inspection of 4800 lineal feet'fofawall eleven feet high. which lwas coated with apparatus constructed -according tothe present invention, did not reveal a singleA shrinkagescrack. Y f

:Another-advantage of the present invention is that 'cementitious materials prepared by the presentl lapparatus vhave been found to have much: higherl compressiveV 'Y strength characteristics..thansimilar material prepared by previously known equipment. Standard. 28 day compressive strength tests by va commerclaltesting laboratory have-indicated strengths of as high as 10,000 pounds per- ;square inch. Also it has vbeen found that a .substantially smaller quantity of waterls required to -give the desired Vdegree of fluidity to the grout than is required ,when the materials are mixed by previously 'known equipment; By way of illustratiomin a onef-toftwo mix, includ.-y insnnepart cementltoftworparts f aggregate', it i sonly necessaryto use 4% gallons of vwater per.

.bagfof'cement whereasin asimilar onerto'.i;w o mili; Preparedfn preYiQuSlv knownequpment. 1t

is pGeSsaryito-use aboutl/z gallons. oft-water per baglof cement to get approximatelythe samefdegrec of fluidity and the resulting'inaterial has an average strength ofabout 3,600 poundspersquare inchv ina standard 28 Yday compressive strength test. These very.` important advantages'made possible by the` apparatus of the `present invention are believed to result from 4more uniform and much higherhydration of the cement particles,-

thanis achievedin previously vknown equipment forthe preparation of cementitious materials;

Now; referring to Figs. 1 and 2 again,an air pressure-line 10 is provided whichleads vto a pres-` suregreducing valve 1I. i Agauge 12 connected 130 approximately 100-y pounds per square inch, it is` apparent that this pressure may be applied to the materialsjin the tank- I5 and that the line may bejcut off at any time by-means of the valve15. Y f i,

. Afterj the material ismixed under pressure in duit 1 tot a second tank 18 also mounted on the bed 10,1 As bestshownbyFig. '1, the conduit 11 includes asleeve containing a rubber tube 8| which'is adapted `to close the conduit to `passage. of fluid therethroughwhen the tube is collapsedv at itscenter. Forcollapsing the tube, a plunger 8 3 is mounted in a small cylinder84 wel'cledto rthe side fof thesleeve and this plunger is adapted to 'be moved downwardly against the wallof thev tube- Bj 'by air pressure at the upper endV ofthe plunger. A spring v85 is adapted to returnthel plungerto its-inoperative position upon release,

of rthe pressure. Y f

Y Referring again to'Figfu'res 1 and'2, thesmall cylinder -84 containingthe plunger 83 is connected to .anair pressure line 81 which in-turn vis con'- nected to the low pressure side of the reducing.l

valve 1l. A manually operated valye 88 islprovided in the line4 81 so that the pressure may be cut off fromthe cylinder 84 and it might be mentioned in this connection that a suitable exhaust;

ventmay be provided in the valve 88 so that when the valvejis closed, air in the lower part of the conduit 8'l and in the cylinder 84 may escape so as thereby to allow the spring to return the.

plunger to its inoperative position. Referring now to Figures 3 and 7, the tank VI8 has a' cover 90 at its upper end which is adapted to vbe firmly held in'closed position Vby a series of circumferentially spaced fastening means which may Vbe lreadily released. Each of these fastening mean s i ncludes a threaded shank 9| pivotally; eonnectedasindicated at 92 to the side Wall/of theta'nk andwhiohmay be-movedinto a slot;4 93 in the edge vof the cover. A wing nut 94 on the end of., the 'shank is adapted to be drawntightly against thecover so as to holdA it in closedposiA tion. A .sealingelement 95 between the edge of the cover and a flange V96 on the tank serves to seal the tank against leakage. Y In order to continually agitate the liquid' coating material in the tank 18, an agitator is vpro,- vided whichincludes a shaft v9'8 journaled ina bearing element 99 fastened in the cover 90 and in a loll/6.1` bearing element I0() fastened to a strap I 0l having its ends welded to the underside ofthe cover Collars |02 above and belowthe strap I0! and fastened `totheshaft, serve to supportand locategthef latter vertically. Blade elements |03 fastened:tthetshaftgfserve' to 'agtater theernateei threaded:y ontornthe'bearin'g element V99' sofas: tot: prevent: leali-age: along tl:1je;slf1aftir andi tha-upper:

meshesnwitha second gean I U6 Thelattei'. 'geen is-'Ymounted" oni a shaftll Il1-which;.as'zbestshownl.

. bracketfflflwelded telfthecover:lIlJ-z ThaoppU-fsite end. of:` the! shaft I 01V." hasa bevelr gear' 'I 09 which meshes with! a bevel -gear' I Ij mountedi on the upper endlof."a's haft III;` Atf itsupper: end'lthiszshaftiisiturnablysupportedin'a shearing? II2 fastenedi to :af-bracket? I I 3 in'Y turn fastenedl t'o'i-,'.tlie-.1side-.ofv4 the tankewhile the' lower endl off trie-.shaft 'is Vjournaled in abearing 'I I5 lfast'enedf,

bybo'lt's I-I Sito -a'splate I :I 15in turn-fastened to the side/members ofi the bed'.!.II1.Y A bevel gear |20' on the'lower` end of thefshaft I I Iv meshesr'withf commen-1 connectedtof-rthe1cyiinderflvz'a of Vthev valve'.anelito' th'eulowpressure side ofJ the reduc'A in@` va'1Ve2:'II i Avalvef IIe-havinga trigger I30 mayfbe used' toi/open: and' close' the-'conduit I215 and thus close and open the gun; Itwill be'- appreciated, however, that 'the' plunger'for closing the'zrubberivalve'might beheld-in a closed positionlby'springr pressure and that a' similar trigger mightibee' used "for movingf the ,plunger-and open-- ingthe valve'.. Y

For'supplyingapressure-to the-grout in tank iili'aiconduit I 3l is bconneeted: to' the'A low 'pressure` side1of-"t`he vreducingvalve TI and this con'- duitt'i'ns turnzV issconnectedi to aconduit I 32`r con'- rreeted to theupperl partVV ef-"the` tank 18:. A; manually..-Y controlledvalveI I S3 in the'conduit' I 32' enables!v cutting-L' oi" the-f air# pressurey from'- the' tank. Y v In; usingitlie.' apparatus.;y described, the proper ingredients Y arel placedin the tank I5;v 'it' being understood thatl'the valve 752 is frst Vclosed and valver-ih''oonduit -'I-'is`- closed.r Then-the cover' 2.1)lisA closed, 'ainline valve-"I5` is; openedj" and` tl'ief'noterf Se# i's 'started so "asitmmixthe" ma;-A teriall under-l pressure-l After?y mixing'the: grout forf asuifloieiit .ti-me, n the 'valv'e'fl-if' mayfbe' closed' so'fasto' open" the 'conduit' 'H and? then' thejmixtureais-lforcedf b'ythe air" pressureA above'it" in' tank-'.15 into1thetank- 1811i After'th'eliquid ma; terial :has been transf erred'Y to `Ltankf'll.; the' valve 88 is again openedsof'a's'Ytoelosetlie conduiti'l and; the; valve@ I 322 then'. maybe opened Vif not opened. previously; to2 place the v liquid? mix in tank "I8 under .they .reducediairf pressure: Fl- Y lowing. this: the'. spray' gun! may bef used foil'applyingv; the'. liquid; to.' thef surfaeel b'e coated: It'imight: be. mentioned at this" tlnieftlriatI normally a'pressure: in' tank Iioff about .siXtyff-poundsf is found'. desirable and hen'ce Y affdi'erential* of afp-'- I proxmately-forty pounds exists between VYth'e'two tank. This: differential-3 .permits th'efrelatively quick? transfer" of fthe lr'nfiXediriaterial" fi-'oml'th'ef mixingrtank; I5 to" th'e-'fsprayingltankf'lih the;I manneiv'a'bovedeseribed y It Willjvbeappreeited tween 3 the pressures ifr the ftanksIY I5l and-"1 83L will"i vary 'dependingfupon'lthe'consistency of italie-mii:j and the'frvsize ofi the conduite-"I1, It"lriasbeen` found# desirable-fte have-thisepressuree differen- The@ above; mentioned" sixty 'pounds pressure't in thespraying tankVJ T8?fmay'also'wary"consiit erablyf depending upen1f1numerousfactorsisuchf ofthe conduit* I25-i andf theelevation' of-'theispra 4-gunj I125*a'b'ove the? level ofi-'the materi'alji ej tank" 13:1 VByjvvay" of'fexam'pl'; ithafshbeenf und thatlwitl'ra' three-Hl quarter ineh hose'fonehundiedfeetflong'apres sure of at least"l thirty pounds-j"perisquareinch plusfthree-quartersf of la" *peundLperv squaref'inch fori each footL ofA elevationrof"the-spray'gun'above: the' level of- 'the material i in" the tank' 18?' vis're" quired '-'to insure` 'proper delivery of" the'v mike'df. material from the tank'l tbith'e" spray 'gun' .'I 2 6'.'

lIt` will be appreciated?ofrecirsejthatL inspray'e' ing f surfaces -at'v 'greatj refievatic'm's''*ab'ove th'e'tan'k; 18* itvmayi' be' necess'aryto*employ' a1' p re'ssure' withinv "the 'tankJ 'I8J 'considerable' greater'. than' the'jaboveomentioned pressure:inth'emixingfftank' I5?- In'fsuch cases"it"'wil l be understoo'dtlia't the pressure;l within the; tank: IS may; bacon? sidera'by' more'. than" one hundred pounds" per" square inch' iiio'rder' to'provide the" desired. dit?" ferenta'l between' the' pressuresfih'tle; tanks; I5

While the'operatbris' using.' the"spray'gun..and` applying the' liquid'. new; ini. tank' T81` ai' 'second-` operator -may 'close the' air valve' Tandexhaust'. air'in' the' -tank by4 mea/nsf ofa' pipe. |352 and.' valve: '|361 Then, while vthe., ist' operatoris'; sprayingwith liqudin tanl.T8',la.neW mixlni be' plaiced'in. the tank ISlLandfpreparedlL new mix may, ble transferred to' tankl. 18`at. any. timeandi event 4 during 'Y operation'. of lthe. spray; gung'. since. itlf`is'l-only," n'eces'sary to elose valve 88. 'tojo'pen conduit" 1.7- and'. thenr the,V dierentiall in.v pressure v,Willforoe.;the 'mire front tanks` I 5r into tank 18. This manner `of..voperatingQtheequipment may.A be .continued indefinitely; and continuousI spraying Y.mayq-thus be` eieoted; f

Wheny it is Adesired torQ-ele'ani-V theeeniipment.'l the .oversmayfbe removed and: the; tanksa vllecl with AWater-"and1 thenethe; covers freplaced: Fol.- 1owin g,this-, ther water- Yin fboth rtanks'f'may' be;4 agitated and the solution then evacuatedzcompletely.; through.. the spray; gunt byfair-v: pressure. Incidentally;i.'lhis` lcleaning;-of.A theel tanks also'. cleans thesspray aun andi-the 'conduit leading; tof'the. latter.V Itymightibez stated'. tuoi thattfif desired;l watempipeehavingj valves; thereinimaybef cormectedftov bothrtanks'so. asf?.tossupplygfWaffe ter, thereto When;desired;.and particularhhtllf the; tanks for: cleaning; .Y Im of`l the n .coyersl-Would notl beinec'essary. to'. place Water in the.; tanks; may." befaddedqthatan' airrescape valves mightdenprovidedtoo on'itankl lesse: that; when;desired; this; tank?" Vcould be openedzxtonthe atmosphere? soz as' to allow' aii'." und'en'pressurezthereinz-to exhau'sti."Y 'l Ansapparats 'constructeda'ecordihgtoLamodified form'.-i of the@ present' invention', isv illustrated mi Figures; 8.a f iiicluisive3 The amparatusA thereniuustrated: neiudes .fsupporugefame generally. designated1V I tlf-*and omprisingf a'f' this event; opening?.-

clutch lever |68,vis provided |56andthedrive'l64.4 Y

$1.19 of spaced .paralleli` longitudinally extending kand relative large tubular membersI .I 42 closed at their opposite ends and interconnected adjacent their forwardends by a pair of parallel, longitudinally spaced, transversely extendingv tubular members |44 and |46. The interior of these transversely extending .tubular members |44 'and |46 .com-

v .municates with'the interior of the longitudinally .extending members |42 to afford a compressed air. reservoir.' Adjacent their rear ends the lon-L gitudinally extendingmembers |42 are securely heldin spaced relation by a transversely extending brace |48.` The frame" 40 isy suitably sup- 'portedon vfront'and rear wheels |50: and |52.re'- fspectively, andV is provided with` a suitable draw bar|54 at its front end. f

A motor generally indicated at |56 and a compressor generally indicated at |58 are mounted on av platform |60 which is supported adjacent the front end of the frame Y| 40 on the transversely extending members |44" and |46. The xcompressor |58 is connected tothe reservoir dened 'by the'tubular members 142, |44 and |46 by a Vline |62 connected to the member |44. Amultiple pulley belt drive |64 is provided for operatively connecting the compressor |58 to the motor 56 'anda suitable clutch |66, 'controlled bya between the motor A cylindrical mixing tank |10, the opposite ends of which are spherically curved' outwardly, 'is clis-` Lposed with its axis extending parallelto the frame -A- members |42 and is mounted on the frame |40 vin spaced'r'elation to the rear end thereof,"by

means of 'brackets |12 and |14. '.Ihe tank |10,

'as best illustrated in Fig. 1l, has a lgenerally tangentiallyv upwardly extending filler neck "|16 disposed midway between itsy ends. Secured to the upper end of the neck |16 is a hopper mechanism'generally indicated-at |18 and comprising a lower'v hopper portion |80 iixedto the upperI end -of the neck`v |16 and provided with a pivotally 'mounted cover |182 Aclosing the'opening atits lower end and adapted to be 4operated by van external handle |84. The hopper mechanism |18 also includes a larger and upper hopper |86- movably mounted on the fixed hopper portion |80 by 4means of cooperatingbrackets |88H andr' |90 mounted on the 'two hopper portions |86and |80, respectively, and receiving through bolts 'l 92. Thev upper `movable hopperfA portion" |86 is resiliently supportedon coilfjsprings |94 disposed 'between the brackets |88 and`|90 and encircling the'bolts |92. 4 An inclined screen |96 is mounted inthe upper hopper part |86vfor sifting all material priorgtocharging it'into the tank |10. A platformV |98 secured to the upper end of the lower fixed `hopper element |80 carriesV a Y vibrator mechanism 200 adaptedto'oscillate the yupper hopper part |86 to sift the materials placed there'- in'V downwardly through the screen1l96. The vibrator mechanism 200 has a forwardly projectling shaft 202 'carryinga sprocket Awheel 204 through which the vibrator mechanism is driven asfhereinafter described. l Atthe opposite side ofthe 4tank |10 fromthel llenneck |16 a water tank 206fisfsuppor`ted` on spaced upwardly extending'v 'brackets 208.-- The Water tank 206 housesv afloat valve mechanism generally indicated at 2'|0 adapted to permit an F accuratelymeasured amount of water to rbesupplied from the water tank 206,V through a line 2 |62 including a valve 2 |4 to a riser' 2|6 i mounted centrally-of the tank 10 atthe upper. sidethereof and` communicatingfwiththe interiorofthe tank. n

l1.0 The iloat valve mechanism may be of a known construction, and' includes an arm 2 1.which may be adjusted to vary the amount of water to be supplied .by the mechanism; In the construction illustrated, the valve 2|4 is a three-way valve permitting water alsofto -be supplied to the tank 206. throughY .the line 2 |2,`from a line 2 I8 having a ho'sev coupling 220 at one endadaptedfor .connection to a suitable water hose, and connected at its other end to the valve2 4; z .g

' .Between-.thespaced bracketsz208,1the tank |10 .is vprovided; with a4 manhole .cover or access yplate 222: of atype conventional in cylindrical tanks,

and havingy a vcylindrical linner surface "forming a lcontinuationiof andpart ofthe cylindrical .in- .,nersurfacepffthe tank.

- .'A secondtank 224,' -but without'the filler neck |16, hopper mechasimiiar to the taak 11o,

nism v|18; and water tank 206, is 'disposed between the tank |10 and the platform |60 and supported on the frame |40 in coaxial relation with the tank |10 by means of cooperating brackets 226V and228. .The tank1224is similarly provided witha manhole `cover 230 'similarto the `manhole: cover- 222 of 'tank |10. Alsofthe tank 224 vis provided with a centrally disposed, upwardly extending riserw232; similartov the 'riser .2:2 6, whichicommunic'ates with theinterior ofthe "tank224 and` to.which 4isconnected a water line 2341having. a .valve 236, and which connects. into .thezwatersupplyl line 2`|8 ahead of the valve 2|4.

'AIhe valvel 236 is normally', closed but may. be opened to supply water to the tank 224 for cleaning it.A 1

A drivey shaft 23s extendsfaxiauy throughihe v'tanks no :and 224 fand issupported at the opposite ends of eachA off the tanks 10 and 224 in stu- -ing boxesf240, hereinafter described "in greater detai1.:1 The shaft 238 is driven fromthe motor |56 through a countershaftl2`42 driven from the motor by a chain" 244 and from which the shaft 238'is' driven through a chain 246. The shafts 238f-and1242 are rprovided with sprocket wheels over whichthe chains 244 and 246 are trained, and whichare proportioned to afford. the v desired Speed-'f I'Oil'loil'of the 'shaft 238. Within each Vof.theitariks""'|10 :and 224,*the shaft 238 carries -a pair. o'f agitator elements 248 rangularly vspaced lgifrdmoneanother. r`Each of .the agitator elements 248 has a'fcontinuou's outer edge/'including Ya v'portio'250, adapted'upon rotation of the shaft 238, to wipe; or move in very "close proximityv to,

.the spherical inner end surface of the tank'to remove any materialtending to adhere to or build up -upon this spherical inner surface. vThe continuousedgelof the agitator'element 248 also includesa..portion 252 adapted, upon rotation of the shaft 238,.to wipe or move in close proximity toj` thecylindrical inner surface of the tank and removematerial adhering to or tending to accumulate upon this surface. Intermediate the edge vportions 250 and252, the continuous edge ofthe agitator element 248 has a smoothly curved edge portion'256 interconnecting.v the edgepo'rtions 250 and 252 andadapted to wipe the annular smoothlycurvedlinner 'surface 258,`by whichthecylindrical'rinner'surface ofthe tank. is connected t0 thesphericalinner end surfaces. The edge 252 Y .isofpreponidnedmharfeach:nasenaxial-exterieur ,fslightly'more: than halfzdf5th'elength-o`f :lineman-k, vthereby? insuring.thatethecomplete' innerfs'urface :of 'theitank :Willibe wiped:duringzeachzevolution lopenaite withithe' centerffsection rto.;deine a fconi' ,tin'uous smooth cylirdricaliinner'smface.

.Referring fin particular ;tol Fig. 12, .zthezabovementioned stumng box e240, lthere'illustralted iin idetail, izcomprises a generally.utubularbodyiil :mountedcin an. :aperture 2262 opening axially through-.the end mall of .the 'tanki `.224. At fitsv :sinner end=thehody 26D fha'szan annuiar-toutwardly extending ange' 2S4'which;.iin-.cooperation with tan annular externalweld .connectingzthe.tank220 an'dthe :.:badyiZiQ :holds the body I2i? 0 'inpla'ce in `the tankwall and .th'eibody and provides; anfannu- :larofseal betweenzthe'body 260 and thetank wall. .-Also :atfits iinnertend fthe body` 250 hasa radially inwardly extending iiange 268 dening a circular 'diameter of theishaft. L'Ihelflange 2'68 tapers fhas'razcylindrical inner :Walk-21.0 .extending outzwardiy -fromthe :danger 2 68'. :to its outer endand A-tfcooperatingwithfthezsh aft .38 :to: define raniannulari chamber,r in the innerportion'fdf Which,=adia :cent athel 'flange 2.68 :is a suitablef'pa'cking material 32:12 i .i This:packingfisicompressed between the .an'ge/ZGB: andV aztubular ipacking,` follower :214

Yhm/.ing sa icylindricalgexterior adaptedto -project ,'into andzcloselyjtihe :inner vWall .21,0 ofthe body n:2.50.1 .Theiad'jacentrfacesl .21B fand 27,3zdf1thezange VV-2i`r8zand themacking fcl'lowerlsz 1:4 'respectivelyfare oppositely 4*inclined -to'gcomprjesrs'rthefpacking :i2-'r2 :toWar'dftheehaft v1238. .'Theiaxially iinneriand Y radially :cuter corner n,ofA Vthe `packing ifollower 2 T4 is-relievedias.indicated at 2:80 "tofacilitate rinseritionaof the packingrfollowerinto the :bod-y 26D. Adjacent its inner -en'd N.the ollower :2114 :hasfa nslight lclearance'with the shaft rZiiand .adjacent 'r .its outerv endgitnarriesia bea-ring 2&2:in*which-:tne vsi'iaftZ'Szis journaled. '..Thebody'26'0, :adjacentits 'outer'iend-is externally 'threaded as 'indicated :at i284 .to freceive.` an iinterna'lly threaded cap 2'86 'Whiiflts vva-.recluced outerfend portion '288 o'fithe packing ffollower F2514- and engages anoutwardly lpresenting shoulder--290jto -mo've the lfollower 12M-inwardly. #I'n'use, the cap '286;isftightened Quntiijasrnau yMeguiar'portion 232 ,of the .packing 'Y '21.4'is jextrudedpaetthe 'radially inneredge of A l@the `,thin V"flange .'Zrthrough the :narrow .annular .opening Yde'iined 'by' vthe A"flange 268 'and Lthe. lshaft audii'chiis provided ia' austera/alize 9 generally Yembodiment,illustraftedinFigs. :l throughi'Z-iinrfclusiire. "The ',value isg'illustrate'd ziinedetail'xin ":Eig. r:lf3,,1cornprises zagflexible Y:tube for esleevefzi providedwithiadapters -Bnilzzatits opposite-ends,

fzwhichihave externallyfzribbedfftubularspurtinns VAment .1362 carries a cylinder 31:2 win'whicnfzis the piston 3M through a line 1:3131- proyided .witir way#ValveY movable vto fone position viter;.venting :the :upper .portioniof thezcylindcr 3132 andshutting o1. .thesupply :of fair- V'to `:the upper side fof the pistonfSfM '-hefpieton emile-.urged itoithe upper :limit Lof :its .travel by af coil :spring 3252 ien- `.circling `the fplunger. 3.1.6 :and .facting -iagainst fthe :lower z.Wal l...of the .oylinderl andftne pis-,ton

. ...ThetankQZ-Mis a'lsogproyidedwithfatdischarge i soigoutletconnection :G 214'.- at .-.the Yforwardcarteci the @tank :adjacent :the low pointAV zthereo .QA suitable line .'or,hosei32.6islconneeted Ato the 4.di-'sfcharge .connection F,32.11; Aand :leads to 'a3-spray fgun 328,;at,itsiothergend y V- .Thefspray-fgun T328 vis r.generally-.sirnilar .to. tl1 e spr-ay gunfl25-of @the Labove'-iiescriloxed .embodi- .ement .illustrated ,in Figs... .1 7 ...inclusive .and-,-simi la'rly .includes .a v.rubber .sleeve valve yof vthe type willustrated .in .Eigs.7 .andl-3, which :is .normally 'held in ithe. .collapsed or fclosed `Vposition .by @air pressure delivered .througnfanzairlinef330 :leading `to (a =valve. 332 .which selectively Kapplies the f-,air pressure .from 4the line 33.0 4 either to fea-.cylinder '33.4 'through :a Lline -.3'36,.for collapsing wthasleaeve Nalve'orlto the nozzle 338 through allinea-:114111. ..cock type .valve r`.34.2 isprovided in Vthe :line .SAB for.. affordingia des'ir'edlcontrol of F,the -volume o'f air Lto be suppliedto the [nozzle 3'3j81throngh 'the';line."340. f

'Refferringf talig. 9, 1.tl'iespray .gun Y`nozzletl comprises 1a' Abody .3M externally threaded4 at. its wouter Aend and 'internally threaded r-atfits `inner end and mounted `on .theouterfend :of the :spray .pack-ing,Y prevents -the pressure Within gtheftank l shaftv 238. yPortionsfoiv thisfinwardly extending section fof, thegpacking.: gradually4 lfall; 01T 'z into fthe -ifand theecap 28 6 iis :periodically tightened ito.

gun328 by an annularzelementdexternally .threaded :for engagement with fthe threaded fin- ,ner .end of Tthe nozzleI-body-:ML .The l.annular .element V345 Iencircles theouter-.end'fpoittion :oir'a .metal fr-.einforcing `.tube :348 zhuusing the :flexible valve sleeve eelement'z350, .through'Wnich'fthe r.cement .grout. :is A'esupplieclz and. ncooperates r ewith itlre '.'reinfcrcingtubei 343 to indenne fan .annular airzchamber. '.lheeairline 5'3210 is connected :at its router .-:end"'to'.ithe -:element i346' and come .municatesywith-ftnefcnaiberzs'sz. '.Afciruemz;

. defined by' the flexible element v366;

; the openings 364.

, I3 zle plate 354 carried in Ithe nozzle body'344 fits (over the outer end of the rubber sleeve 350, which in the construction illustrated terminates'in an outwardly turned flange portion 356fhavi'ng1a plurality of axially extendingapertures 358. com- -municating with the annular air chamberg352. 'The nozzle plate 354 has an inwardly projecting centralv portion 360 which fits within the .rub-

"ber sleeve 350. `anddeiines a. conical central openingV 362 therethrough., The outer'marginal' lportion of the nozzle plate 354 is'provided with a plurality of Vequally angularly spaced radially inwardly inclinedv openings 364v registering at 4one end with the openings 358,'and veach 'adapted to direct a jet of air" from the air chamber 352 at a' predetermined point on the axison the vber 368 maybe moved axially ofthe nozzle body 344 by means :of its .threaded engagementv with the` nozzle body, and upon suchaxial movement .relative to the nozzle body is eifective,V as here- -inafter described,` to vary the sizez' of 'theorillce At-its in- -ner end, the flexible element 366 lhasan `out- .wardly extending annularxilange` 31|)` gripped between a cooperating shoulder on vthe nozzle body 344 and an outermarginal portion of the Vinnerface of the nozzle plate 354, outwardly of vSpaced inwardlyifrom its out- .er end A,the body'344 has anannular --inwardly extending vprojection defining anwoutwardly. presentingannular shoulder '312; 1' Yy.y .i

- AThe flexible. orifice element` 366,'in1itsfreefor undistorted condition, has an innercylindrical surface 314 defining the desired-maximum orice opening and extending from a, point axially inwardly of the shoulder 312 to the outer end-of the element 366. The radially youter surface of the element .366 is shaped to provide an -annular radially outwardly extending.` projection' 316 adapted to engage the shoulder 312, a sealing ange portion `318i at theouterl end of the element 366, and an intermediate radially outwardly extending annularportion 3-80 which, uponn compression axially, cooperates injvarying. the Vsize -of the orifice defined `by the element 366. In the ynormal or free vcondition ofthe elementr366, Ythe sealing flange 318 extends-radially and axially outwardly. 1 Upon assemblyof thegnozzle 338,

.the flange 318 isengaged byan annular` element element 382 has an inclined inner surface 384 cooperating with-the shoulder 312 upon movement of the member 368 axially inwardly to'deformytheinner surfaceof the element 366 to some position such as -that illustrated -in'broken lines .in .Figure 9,',thereby -reducing the orifice-size.

7 The element 382 isadaptedto move into the outer end of the nozzle body 344-upon movementof the member 368" axially inwardly from the posi- .-ton` pf. maximum orifice opening illustrated Vin 9. Also; the Vannular element 382 hasl an raxially.-inwardly extending flange 386 at its radially outer. edgewhich. presses the outer portion of the projection 380 into;the outer end of thevnozzle `body 344'and cooperates in deforming theelement 366radially inwardly.v 1.

l It will be appreciated that any suitable airline systemv may be provided for'sup'plying the desired air pressures from'the compressed air reservoir provided bythe frame members |42, |44v and |46, tothe tanksj |10 and l224 andthe lines 3|8 yand 330 .leading respectively to the transfer valve 29.6, and the'spray gun 328. In the embodiment illus-- itrated in Figures 8-.-13the line 330 :leading to ithe spray gun '328 is connected directly to the K compressedair reservoir member` |42 ljust rearwardly of the engine |56 through anv alrpressure gauge v38-8,V a pressure-reducing valve 390 vand-1a line 392. As-an instance of a satisfactory' prssure in the llne330`for operating'th'e spray-gun 328, vit has been found that a pressure of$60 pounds per square inch in the line '330 givesgood results. i

Air under pressure Vis supplied'frorn thefre'sr- Voir provided by thev frame |40 tothe linevl3`|8 leading to the valve 296 and. to the tanks -|10 and 224 through their risers 2 I6 and 232 respectively, through the Vfollowing briefly-described air line system. An air pressure supply line 394 runs from a reservoir member |42 toV a pressure reducng'valve 396. Air pressure is supplied tothe tank` |10` through ta line 398 connectedvtov the valve 2 I4. is returned .to its closedvposition', Aften vclo'singthe hopper cover |82-by means of `th Ariser 2 ll'at` one 4end and including an airV pressure gage ,400 and a valve 402, and connected at `jits other end into'the line 394`at`the high pres- /sure side of the reducingvalve 396. Air pressure is suppliedv to the; tank "224 through aline' 404 connected at one endg to the riser 232 andy'including an airv pressure gage 406 and a valve408,

andf having 'its other end connectedto' theiqw pressure side rofV74 the reducing ,valvef'396lv -j-Air pressurev is supplied tothe valve-'296i through the line 3|8 which includes'the valve 32 0', and yis connected intothe airpressure supplyfline' 319,4

,at'the high pressureside ofthe pressurereduc ingA valve 396.1,As mentioned above, with referencelto the valve 320, the valves 40,2' and 408 are three-'way valves connected to a vent line 4|0 sov that the tanks A|10 and 224, aswell as the upper portion of the piston cylinder 3|2 of the valve 4296 may be desired. l v

The sprocket Wheel 204 ofthe above-described vvibrator mechanism 200 is driven through a chain vented to atmosphere when 4|2 -trained overl-the sprocket'wheel 204 and also trained over a sprocketwheelxed on'the shaft 236 intermedatethe tanks |10 and 224. g y

Thej 'operation vof the embodiment illustrated inFigs, 8 through 13,V inclusive, is generally similar to that yof the embodiment illustratedfin Figs.

I1 through "I, inclusive, and briefly stated isas follows". The desired proportions of thedry ma- `terials are placed in the hopper mechanism' |18 from which they are dropped into the tank`7|10 by loperation of the lever |84. During this loading-'of the tank |10 the air valve 402 isturned to `vent-the'interior of `the tank |10 to atmospheric pressure through the vent line` 4|0. lsopriorto charging the tank |10, the valvel 3 20 v'should'be 'turned tother positionin which airpres'sure is applied to the valve 2961oollapsing) thefsvleeve'2`98 and closing the line 294. At the time of charging the dry materials into the tank |10, the vvalve 2|'4 is opened, permitting an accuratelyv measured amount of Waterto drain from the lta'nk206 into the tank |10. After the flow of Water cea'se'sythe ition'fi'n Which-.'air pressurefis rsupplied :from the .,Jreducing .valve 3.95: iand :the #materials Within Ythe tank [110 fare mixe'dfan'l :agitated by the vagitator elements 2148 While-'being .continuously*subjected Vtofthis:pressurelforfa .desired length of :.time. As

mnrins'tance of asatisfactorymixingiperiodwhich :hasrbeenf'found ,totaiord-the advantageousresults s indicated herein,itfhasz.beenfcundthataiperiod zofii'fwoifminutes'maybe used. -At ther-endpfthis stofatniosphere .through the lined I 0, or in a posi- -tion infwhich'the:upperwside of the-vpiston (450i the valve -is ventedY .toatrnosphere .throughthe 'filme-4 Hinwhich permits thesprng3-22 to4 raiseithe "tplunger 3I'6,opening the sleeve .298, andgperm'itting the air pressure within the tank ITU toqforce --the :material Y therein -.throughs-the` line .2 84 :and y:

-fithe-valve1-296 into-.thef=tank 22f4.,yDuring-the jnitialL transfergioperation, the f'airfline .-valve 488 `.-ma'yf.either be 'in afposition-vventing theftank-224 ::tatmosphericvthroughatheline-4 l D,` or in -a vposi- .ation vconnecting it vto the low pressure- .side-.of Ithe f,.p1eted,.the vali/e320 :is returnedv to .the position I.in whichppressure vis applied 4to-..the .valvea296 v.sure'thereinl is..relieved anotl'ierbatch` of material zmayloe-charged into ,the :tank I 10.,.fromthe hopfper mechanism 1F18 and .the proper .amount of v Water Supplied theretolby:openingfthe'valve 2 I4. ,A`fter the hopperrdoor |.82 is againrreturned 'to v;thef.closed `positionby .the lever I 84.,and the VWater line valve '214 is again closed, the airline 4,02 Arues/'lue again turned rto the .position in which the-.tank |10 .is.,directly connected to .the '.high pressure :side of Lthe .pressure -reducing V.valve Yv 3 9 E andlanothervbatchmay bemixed inthe tanki'l While thev formerbatch is being sprayedlfrom the ltank V224. Whenthefmixing,intheltank H0 is completedfand while the. spraying from' the tank z2-.Lis continuing, the valve 320fmaybe turnedto .open 4.the vtransfer valve v296 land the .pressure .differential in the tanks :i 70 and`224, lcorrespondingftothepressure diierential between the Yhigh .andlow .pressure sides of the pressure reducing :valve-396,Will be effective toquicklytransfer the second-batchof mixedmaterial from the-tank |10 V-.tojhetank 224. Itvvill thus befappreciated that V.the.apparatus of .this embodimentialsopermits y.continuousfoperation.s i

4While Vonly two yspecirc Lembodimentslof l.the tinventionhave Vbeen illustrated and. described in vdetail, .it will vbe readilyappreciated 'by .those 3ski1ledin,the;a rt that various modication'sland 'echanges may -be made Without departingfrom vthespirit;of:thepresent:invention.

"Whatisaclaimed is: 1;.Y f 51. An apparatus forl preparing cementitious materials Whioln` upon setting,- Willibeisubstan- `tially free '.ofzshrinkage '.'cracks and lhave greatly :appease .2396,t ,thefairvline valve-402may .be turned 'to vent..40.'

` thetanklf'm to atmosphereandafter the pres- 16 timproved:strength, said apparatus being f'adapted ."formixinga groundf'argillocalcareous material, Waten'fandian aggregate to rapidlyefect-arelatively ,'highk and uniform hydration vof "saidimate- ,.stantially yuniformly .mixed .cementitious mate- Trial` including groundfargillo-ca'lcareousmaterial fso vhydratedfeand van 'aggregate, 'said lapparatus comprising `a :mixing ',tank, means V.for ifagitating Y andmixing the"v contentsfof "saidtank, means 'for `vapplying "a vpressure substantially fabove'zatmosphere to i-the Acontents of said .tank duringfthe- ,mixingoperatiom 'a second j'tank adapted vto receive the .liquidfmixtconduit Ameans connecting and; have greatly :improved 'strength,r said fapparati-is being ,adapted for :mixing aground argille-calcareous kmaterial,"1vvater,:and fan aggre- -gate Lto irapidly eectxa relatively 'high 'and vuni-- form hydration'of '-'saidrmateriaL vfor supplying a Vcontinuous 'oW fof substantially '-unifornily mixed cementiti'ous material includingf'ground argillo-lcalcareous material so 'fhydrated fand "an aggregate; 'and for v putting "the mixedl cer'nentitious material in placeysaidfapparatus comprisingifalmixing 1tank, means forfagitating an'dlmixing fa pressure-substantially above atmosphereto the contentsfof said tankeduringfthe mixingfoprerati'on, fa second tank adapted to receive `the liquid mix,V conduit meansfconnecting said'tanks Vso' that ithe 'liquid mixmay'be transferred' from :said .mixingk ftazik lto fsaid "second vtank, 1valve means "foropening'and v'closing said conduit vmeans, meansffor fagitati-ngithe liquid mixfin said secondy tankrgmeansjincluding other conduit means connected to fsa'id *secon'd'tank fior putting the mixed l"cer'nent'itious .material in place, and 'means V:for applyingto thecontentsof vsaid second 'tank Ja pressure substantiallylower 'than -sai'd pressure but substantially above atmospheric pressurefso that a desired pressure differential 'may f bel established @which Imay 4be employed totransf' fier the liquid mix 'from the mixing 5tarik'to "the y=see'o`r1d' tank fwithout yeducii'ig Athe V-`pressureiin said second tank. Y l y IBLAnjapparatus for .preparing andspra'ying "cementitious vrmaterialswhich, upenn-setting,l LWill be 'substantiallyA` free v'of r'shrinkage cracks 'fa'nd jh'ave. greatly' improved `strength, f said apparatus Nbeing adapted for mixing aground 'v-argillo-'caloareous material, wateryan'd an faggregate y"to Iesure substantially-:aboveatmosphere ftofthe conrial and for Asupplying va-'continuous flow .of lsubsaid Y.tanks Vso tthat the liquid `mix vmaylbeztrans- .ing ith'econtents f said tank; means fior" apply- Y 17 tents of said tank during the mixing operation, a second tank adapted to receive the liquid mix,

.conduit means connecting said tank to said second tank, valve means for opening and closing saidl conduit means, means including other conduit means connected to said second tank and a spray gun connected to said other conduit means for spraying the mixed cementitious materials, and means for applying to the contents of said second tank a pressure substantially lower than said pressure but substantially above atmospheric pressure so that a desired pressure differential may bev established which may be employed to transfer the liquid mix from the mixing tank to the second tank Without reducing the pressure in said second tank.

4. An apparatus for preparing and putting in place cementitious materials which, upon setting, will be substantially free of shrinkage cracksy and have greatly improved strength, said apparatus being adapted for mixing a ground argillo-calcareous material, water, and an aggregate to rapidly effect a relatively high and uniform hydration of said material, for supplying a continuous flow `of substantially uniformly mixed cementitious material including ground argillo-calcareous material so hydrated, and an aggregate, and for putting the mixed cementitious materials in place, said apparatus comprising a mixing tank, rotary means for agitating and mixing the contents oi said tank, means for applying a pressure substantially above atmosphere to the contents of said tank during the mixing operation, a second tank adapted to receive the liquid mix, conduit means vconnecting said tank so that the liquid means may be transferred `from said tank to said second tank, valve means for opening and closing saidv conduit means, rotary means for agitating the liquid mix in said second tank, means including other conduit means connected to 'said second tank for putting the mixed cementitious material in place, means for applying to the contents of said second tank a pressure substantially lower than said pressure but substantially above atmospheric pressure so that a desired pressure differential may be established which may be employed to transfer the'liquid mix from the mixing tank to the second tank without reducing the pressure in saidsecond tank,

and common motor driven means for drivingy both agitating and mixing means.

5. An apparatus for preparing and putting in place cementitious materials which, upon setting, will be substantially free of shrinkage cracks and have greatly improved strength, said apparatus being adapted for mixing a ground argillo-calcareous material, water, and an aggregate to rapidly effect a relatively high and uniform hydration of said material, supplying a continuous flow of substantially uniformly mixed cementitious material includingv ground argillocalcareous material, so hydrated, and an aggregate, and putting the mixed cementitious materials Lin place, said apparatus comprising a mixing tank adapted to withstand an internal pressure of at least 100 lbs. per square inch, means for agitating and mixing the contents of said tank, means for applying a pressure of at least 100 lbs. per square inch to the contents of the tank during the mixing operation, a second tank adapted to receive the liquid mix and to withstand an internal pressure of at least lbs. per square inch. conduit means connecting said tanks so that the liquid mix may be transferred from said mixing tank to said second tank, valve means for opening and closing said conduit means, means for agitating and mixing the liquid mix in the second tank, means including other conduit means connected to said second tank for putting the mixed cementitious materials in place, and means for applying to the contents of said second tank a pressure of at least 60 lbs. per square inch, but substantially lower than the pressure applied to said mixing tank so that a desired pressure differential may be established whichr may be employed to transfer the liquid mix from the mixing tank to said second tank without reducing the pressure in said second tank.

WARREN G. BROWN. WARREN DURAND BROWN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1 851,603 Long Apr. 23, 1907 991,814 Akeley May 9, 1911 1,024,221 Osgood Apr. 23, 1912 1,223,586 Johnson Apr. 24, 1917 1,323,663 Weber 'Dec. 2. 1919 1,785,024 Evans Dec. 16, 1930v 1,810,271 Fraenkel June 16, 1931 1,997,897 Couley Apr. 16, 1935 2,067,105 Stevens et al Jan. 5, 1937 2,073,779 Bramsen ,Mar. 16, 1937 2,137,328 Bissell Nov. 22, 1938 2,149,930 Plastaras Mar. '7, 1,939

2,165,916 Bissell July 11, 1939 2,238,051 Hackley Apr. 15, 1941 2,259,215 Schuerer Oct. 14, 1941 2,305,840 Brown et al. Dec.y 22, 1942 Kiggins Jan. 9, 1945 

